1. Field of the Invention
This invention relates to an insert, hereinafter referred to as the kind described, for placement within a vessel such as a tube to contact fluid therein.
Where the tube is a heat exchange tube for heating or cooling a fluid flowing through the tube the insert improves the efficiency of the heat transfer. For example, in the case of cooling a first fluid flowing through a tube by a second fluid on the outside of the tube the heat flux is given by: EQU Q=A h T (I)
where
Q=heat flux PA1 A=area of the inside of the tube wall PA1 h=film coefficient of the rate of heat transfer from the first fluid to the wall. PA1 T=temperature difference between the first fluid and the wall (log mean T)
The film coefficient h is influenced by a number of factors:
(1) The turbulence of the first fluid both at the wall of the tube and within the tube away from the wall
(2) The turbulence of the first fluid around the insert.
(3) The additional turbulence of the first fluid at the wall by the baffle action of the insert in contact with the wall.
(4) The nature of the material of construction of the insert and the rate of heat transfer by conduction along the insert to the wall.
(5) The rate of heat transfer across the junction at the point of contact of the insert with the wall. If unsoldered, with a micro film of fluid between the point of contact of the insert with the wall, the ability to conduct heat away from that transferred from the first fluid to the insert is less than when soldered. Soldering apart from eliminating the fluid film also marginally increases the area of contact with the wall thus creating an improved path for heat conduction.
(6) The more effective the conduction in transferring heat along the insert to the wall the lower the temperature of the insert and thus the greater the T between the first fluid and the insert surface. This improves the heat flux to the insert.
Where the vessel is a fluid treatment apparatus such as a fluid-fluid or fluid-solid contacting, de-entraining or physical and/or chemical reactor vessel, tube, column, tower or the like, an insert or a plurality of inserts of the type described is or are provided to improve, for example, one or more of the following; mixing, separation or distribution of fluids, mixing separation or distribution of a fluid and a solid, increasing the rate of diffusion or permeation in tubes used for reverse osmosis and permeation de-humidification coalescence and the like.
The above uses of an insert of the type described are given by way of example and explanation only and are not to be regarded as in any way limiting of the scope of the protection to be afforded by this patent since an insert of the type described and embodying the present invention may have other uses.